Any prenatal alcohol exposure may cause adverse effects among offspring

Any amount of prenatal alcohol use was associated with subtle but significant psychological and behavioral effects among offspring, according to study results published in American Journal of Psychiatry.

“Although there is an established literature on the adverse outcomes associated with heavy alcohol use in pregnancy, evidence of the effects of lighter alcohol use [i.e., fewer than seven drinks per week] on offspring psychological, behavioral and neurodevelopmental outcomes is sparse and inconsistent, perhaps because of sample size and inadequate adjustment for potential confounding factors in some studies,” Briana Lees, B.Psych. (Hons), of The Matilda Centre for Research in Mental Health and Substance Use at the University of Sydney in Australia, and colleagues wrote.

The investigators sought to address research gaps of prior studies by conducting the current retrospective study, in which they assessed associations between mothers’ reported prenatal alcohol use and psychological, behavioral and neurodevelopmental outcomes among 9,719 substance-naive youths aged 9 to 10.9 years who were included in the Adolescent Brain Cognitive Development Study. According to parental-reported data, 2,518 (25.9%) of these youths had received alcohol exposure in utero. The researchers used multilevel cross-sectional and longitudinal mediation models, as well as generalized additive mixed models, to determine whether this exposure was linked to psychological, behavioral and cognitive outcomes, and whether structural brain differences and resting-state functional connectivity played a role in these links at baseline and 1-year follow-up, after they controlled for possible confounding factors.

Results showed an association between any severity of prenatal alcohol exposure and increased risk for psychopathology, attention deficits and impulsiveness. Certain effects exhibited a dose-dependent response. Compared with those without prenatal alcohol exposure, those with exhibited greater cerebral and regional volume, as well as greater regional surface area. Children with in utero exposure had largely unaltered resting-state functional connectivity. At baseline and at 1-year follow-up, certain psychological and behavioral outcomes appeared partly linked to differences in brain structure among those who had in utero alcohol exposure.

“Examination of dose-dependent relationships and light alcohol exposure patterns during pregnancy shows that children with even the lowest levels of exposure demonstrate poorer psychological and behavioral outcomes as they enter adolescence,” Lees and colleagues wrote. “Associations preceded offspring alcohol use and were robust to the inclusion of potential confounding factors and during stringent demographic matching procedures, increasing the plausibility of the findings. Women should continue to be advised to abstain from alcohol consumption from conception throughout pregnancy.”